Over the past decade, much research has been devoted to developing new and useful devices for delivering beneficial agents to agent receptor environments of use. The traditional manner of administering sustained parenteral treatments is an intravenous drip. While this may be perfectly acceptable in a hospital environment, it is obviously imposes severe restrictions on the activity of the recipient. As a result, considerable research over the last few years has been devoted to the development of small portable infusion pumps.
A range of devices has appeared, including those with electric motors that drive pumps, and others powered by an osmotic engine. While these delivery techniques are being used, they have certain disadvantages. For example, the use of electromechanical pumps is expensive and sometimes inconvenient because of their size and weight. The use of an osmotic pumps, while small in size and requiring few moving parts, is slow in start-up time.